The general idea of reacting a diacyl derivative of a bisphenol or glycol with a diester of a carboxylic acid to form a polyester has been disclosed in Polymer, Vol. 15, pp. 531-532; in U.S. Pat. No. 4,075,173 (columns 2 and 3); and in U.K. Pat. No. 590,417. In the first two references only oligomeric materials were obtained when bisphenol A diacetate was reacted with dimethyl terephthalate. In the U.K. patent, high molecular weight poly(alkylene terephthalates) are disclosed with no reference to aromatic diols.